Notary Project

The Notary Project is a CNCF incubating set of specifications and tools for signing and verifying container images and other OCI artifacts. It provides Notation, a CLI and library for signing artifacts stored in OCI-compliant registries. The project defines standards for signature formats, trust policies, and verification workflows to secure software supply chains.

Notary Project publishes 4 APIs on the APIs.io network. Tagged areas include Cloud Native, Container Security, Image Signing, Incubating, and OCI.

The Notary Project catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

Notary Project’s developer surface includes documentation, getting-started guide, engineering blog, FAQ, changelog, and 9 more developer resources.

🌐 Visit website 📡 Source on GitHub

41.8/100 thin ▬ flat Agent 3/100 human only Full breakdown ↓
scored 2026-07-28 · rubric v0.6

AccessFreemium

4 APIs

Cloud NativeContainer SecurityImage SigningIncubatingOCIVerification

Kin Score

Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6

Composite quality — 41.8/100 · thin

Contract Quality 8.5 / 25

Developer Ergonomics 4.3 / 20

Commercial Clarity 7.9 / 20

Operational Transparency 6.8 / 13

Governance 7.0 / 12

Discoverability 7.2 / 10

Agent readiness — 3/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/notary: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 4

Individual APIs this provider publishes, each with its own machine-readable definition.

Rate Limits 1

Documented rate limits and quota policies.

Notary Rate Limits

5 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

JSON Schema 4

Standalone JSON Schema definitions for this provider's data models.

Get Started 1

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

Documentation 5

Reference material describing how the API behaves

Documentation

JSONSchema

JSONSchema

JSONSchema

JSONSchema

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

JSONLD

JSONLD

Build 2

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

GitHubRepository

GitHubRepository

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Operate 2

Status, limits, changes, and where to get help

FAQ

FAQ

ChangeLog

ChangeLog

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: notary
name: Notary Project
description: The Notary Project is a CNCF incubating set of specifications and tools for signing and verifying container images
  and other OCI artifacts. It provides Notation, a CLI and library for signing artifacts stored in OCI-compliant registries.
  The project defines standards for signature formats, trust policies, and verification workflows to secure software supply
  chains.
url: https://notaryproject.dev
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/notary.png
tags:
- Cloud Native
- Container Security
- Image Signing
- Incubating
- OCI
- Verification
created: '2026-03-16'
modified: '2026-04-28'
specificationVersion: '0.19'
type: Index
apis:
- aid: notary:notary-spec
  name: Notary Project Signing Specification
  description: The Notary Project specification defines the signature envelope format, trust store and trust policy for container
    image signing and verification. It supports multiple signature formats and integrates with OCI distribution registries
    for storing signatures alongside container images. The specification enables end-to-end supply chain security from build
    to deployment.
  humanURL: https://notaryproject.dev/docs/
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://notaryproject.dev/docs/
  - type: Reference
    url: https://github.com/notaryproject/specifications/blob/main/specs/trust-store-trust-policy.md
  - type: GitHubRepository
    url: https://github.com/notaryproject/specifications
  - type: JSONSchema
    url: json-schema/notary-trust-policy-schema.json
  - type: JSONSchema
    url: json-schema/notary-signature-envelope-schema.json
  tags:
  - Signing
  - Specification
  - Verification
- aid: notary:notation-cli
  name: Notation CLI
  description: Notation is the command-line tool that implements the Notary Project specifications for signing and verifying
    OCI artifacts stored in container registries. It supports signing with certificates stored in trust stores, configuring
    trust policies for verification, and extends to third-party key management systems via a plugin model.
  humanURL: https://notaryproject.dev/docs/user-guides/installation/cli/
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://notaryproject.dev/docs/user-guides/installation/cli/
  - type: GettingStarted
    url: https://notaryproject.dev/docs/user-guides/installation/
  - type: Reference
    url: https://github.com/notaryproject/notation/blob/main/specs/notation-cli.md
  - type: GitHubRepository
    url: https://github.com/notaryproject/notation
  - type: ChangeLog
    url: https://github.com/notaryproject/notation/releases
  tags:
  - CLI
  - OCI
  - Signing
  - Verification
- aid: notary:notation-go
  name: notation-go Library
  description: notation-go is the official Go library for signing and verifying OCI artifacts using the Notary Project specifications.
    It provides the programmatic interface used by the Notation CLI and enables Go applications to integrate artifact signing
    and verification into their own workflows without invoking the CLI directly.
  humanURL: https://github.com/notaryproject/notation-go
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://pkg.go.dev/github.com/notaryproject/notation-go
  - type: GitHubRepository
    url: https://github.com/notaryproject/notation-go
  tags:
  - Client Library
  - Go
  - SDK
  - Signing
- aid: notary:notation-plugin-framework
  name: Notation Plugin Extensibility
  description: The Notation plugin extensibility specification defines the interface that third-party plugins must implement
    to integrate with Notation for key management, signing, and verification operations. Plugins allow Notation to work with
    hardware security modules, cloud key management services, and other external credential systems.
  humanURL: https://github.com/notaryproject/specifications/blob/main/specs/plugin-extensibility.md
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/notaryproject/specifications/blob/main/specs/plugin-extensibility.md
  - type: Reference
    url: https://pkg.go.dev/github.com/notaryproject/notation-plugin-framework-go/plugin
  - type: GitHubRepository
    url: https://github.com/notaryproject/notation-go
  - type: JSONSchema
    url: json-schema/notary-plugin-schema.json
  - type: JSONSchema
    url: json-schema/notary-plugin-protocol-schema.json
  tags:
  - Extensibility
  - Key Management
  - Plugin
  - Signing
common:
- type: DomainSecurity
  url: security/notary-domain-security.yml
- type: Website
  url: https://notaryproject.dev
- type: Documentation
  url: https://notaryproject.dev/docs/
- type: GettingStarted
  url: https://notaryproject.dev/docs/user-guides/installation/
- type: Blog
  url: https://notaryproject.dev/blog/
- type: FAQ
  url: https://notaryproject.dev/docs/faq/
- type: GitHubOrganization
  url: https://github.com/notaryproject
- type: GitHubRepository
  url: https://github.com/notaryproject/notation
- type: ChangeLog
  url: https://github.com/notaryproject/notation/releases
- type: JSONSchema
  url: json-schema/notary-trust-policy-schema.json
- type: JSONSchema
  url: json-schema/notary-plugin-schema.json
- type: JSONSchema
  url: json-schema/notary-plugin-protocol-schema.json
- type: JSONSchema
  url: json-schema/notary-signature-envelope-schema.json
- type: JSONLD
  url: json-ld/notary-context.jsonld
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

Notary Project

Kin Score

APIs 4

Notary Project Signing Specification

Notation CLI

notation-go Library

Notation Plugin Extensibility

Pricing Plans 1

Notary Plans Pricing

Rate Limits 1

Notary Rate Limits

FinOps 1

Notary Finops

Semantic Vocabularies 1

Notary Context

Spectral Rules 1

Notary Project API Rules

JSON Schema 4

Notary Project Plugin Protocol

Notation Plugin Protocol

Notary Project JWS Signature Envelope

Notary Project Trust Policy

Security Posture 1

Notary Domain Security

Resources

Get Started 1

Documentation 5

Design & Contract 1

Build 2

Access & Security 1

Operate 2

Company 2

Source (apis.yml)